The following season, Tom was a permanent fixture in the Ireland under-20 team for the six nations and the Junior World Championship in Japan.

He also captained this side on a couple of occasions, a team containing current Ireland internationals, Peter O'Mahony, Ian Madigan and Conor Murray.

He made eight appearances for Leinster's Senior team under Joe Schmidt, his debut coming against Connacht on New Year's Day 2011 in the Pro12 League.

In June 2016, Tom was a member of the Western Force team that won the World Club 10's tournament in Mauritius.

In October 2015 it was announced that Sexton had signed a deal with The Western Force for the 2016 Super Rugby season.